The 2N3055 power transistor was introduced by the Radio Corporation of America (RCA) in the early 1960s. It was one of the first silicon power transistors, offered unrivalled second breakdown immunity and found many applications particularly in audio power amplifiers.

It was 225WRMS, they no longer do it.
Shame it was a good solid amp.
I am sure i have seen a picture of it on this forum at some time.

I remember it though i never bought one

It used MJ2955 as the pnp compliments & a +/-55V approximately power supply. Lord knows how it didn't blow up as you can see the rail voltages were well in excess of the VCE of both the 2N3055 & the MJ2955. I guess they were relying on the reverse biasing of the output transistors to stop them exploding

The CM Labs 911 was among the very first commercially built solid state amps that made the unheard of power output of 100wRMS. It is a quasi complementary output stage with a big cap blocking DC. Nice amp actually.

The other amp of the day, that was also quasi complementary was of course the Dyna ST-120.

There really were not a lot of powerful solid state amps before 1970.

_-_-bear

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_-_-bear http://www.bearlabs.com -- Btw, I don't actually know anything, FYI -- every once in a while I say something that makes sense... ]

Back in those days, lots of amp makers would cheat by putting 2N3055's, 2N3772's etc. on a curve tracer and see if they took the 100+ volts they needed. The epitaxial versions usually would (now they just call it an MJ15015).